1. Technical Field
The present invention relates to a nozzle inspection device in a fluid discharge apparatus which inspects presence of a defective nozzle which becomes incapable of discharging the requisite amount of fluid due to nozzle clogging of a discharge unit by discharging fluid from nozzles, a fluid discharge apparatus, and a nozzle inspection method.
2. Related Art
From the past, in an ink jet printer which is a kind of the fluid discharge apparatus, printing to a target, such as paper, is performed by discharging ink from nozzles of a recording head (discharge unit). If ink in the nozzles was thickened or air bubbles invaded into the ink, the defective nozzle which cannot discharge the requisite amount of ink arose, bringing about the dead pixel in a print image.
Accordingly, a nozzle inspection device which inspects presence of this kind of defective nozzles is disclosed. Therefore, according to JP-A-59-178256 and JP-A-2002-79693, when the nozzle inspection device detects the defective nozzle, a cleaning comes to be performed with respect to the nozzles of a recording head.
For example, in the nozzle inspection device (nozzle clogging detection device) disclosed in JP-A-59-178256, the recording head (ink jet head) serves as a first electrode, a second electrode is disposed at a side wall facing the recording head in a nozzle covering hole of a capping member, and a voltage is applied between the first and second electrodes by a power supply. In such a state, charged ink droplets are ejected from the recording head, and an electric field detection portion which detects a change of an intensity of an electric field between the first and second electrodes which is attributable to the passing of the ink droplets is disposed.
JP-A-2002-79693 discloses a laser nozzle inspection device which inspects presence of the defective nozzle by detecting light interception of laser light, emitted toward an ink traveling pathway, which is attributable to the ink droplets discharged from the nozzles. JP-A-2002-79693 further discloses a nozzle inspection device using a vibrating plate inspection method for inspecting the dead pixel by checking presence of a vibration of a vibrating plate which is attributable to the ink droplets when the ink droplets are discharged to the vibrating plate.